mctighe



CNC Model.)

ZSheets-Sheet 1.

J. J. 8v T. J. MCTIGHE.

DYNAMC ELECTRIC MACHINE.

Patented Jen. 9,1883.

N4 PETERS. Pholfvlilhognpher, Walhinian. D. C

v(No Model.) 2 Sheets-Sheet 2.

` J. J. & il?.v J. MOTIGHE.

` DYNAMO ELECTRIC MACHINE.

No. 270,325. l Patented Ja.11.9,1883.

N. PETERS, inuIu-Umngmplvcr. washington, D. c.

UNITED STATES PATENT OFFICE.

JAMES J. MCTIGHE AND THOMAS J. MGTIGHE,IOF PITTSBURG, PA.

DYNAMO-ELECTRIC MACHlNE SPECIFICATION forming part of Letters Patent No.270,325, dated January 9, 1883.

(No model.)

To all whom it may concern- Beit known that we, JAMEs J. MoTIeIIE andTHOMAS J. MC'lIGHE,ot' Pittsburg, in the county ot' Allegheny and State0l' Pennsylvania, 'have invented certain new and useful Improvements inDynamo -Electric Machines; and we do hereby declare that the followingis a full, clear, and exact description thereof, which will enableothers skilled in the art to which it appertains to malte and use thesame, reference being had to the accompanying drawings, which form apart of this specification, in which Figui-e1 is a longitudinal verticalsection of a machine embodying ourimprovements. Fig. 2 is a transversevertical section of the tieldmagnet.

'lhis invention relates to the construction of eld-of-t'orce magnetst'or dynamo-electric machines; and itconsistsin arranging the magnet inthe form of a tubular magnet in which one end ot' the core constitutesone pole, and the other pole is an extension of an iron tube sui'-rounding the coil and magnetically joined to the other end ofthe core,substantially as hereinafter described aud claimed.

A is the core, having the curved pole-piece B t-o partially embrace thearmature U. Gorev A is titted and bolted to the bottoni a ofthecylinder-D of iron. Before bolting these tothe curved polar facediametrically opposite therpole-piece B ot` core A, and between thesethe armature is located and revolves. The result is that the inductiveinfluence ot' the cur rentis utilized ootli inside the coil on the coreAand outside 0n the cylinder D, and the magnetic tield is concentratedpowerfully between B and Gr, and external magnetism will not exist toany serious extent; and this ei't'ect is produced by a singleenergizing-coil, F, so that the total inductive ell'ect ot' a givenamountot' wire can be concentrated in a small space and renderedavailable as active magnetism.

We claim as our inventionl. In a dynamo-electric machine or electricmotor, a single energizing-helix, in combination with a core of iron,one end ot' which terminates directly in a pole-piece and the other endof which is expanded in the form of a cylinder, returning outside thecoil and terminating in a second pole-piece opposite the first,substantially as described, the fieldotforce being thus located betweensaid polepieces.

2. The combination ot" coil F, core A, having pole-piece B, bottom o,cylinder D, cheeks d, and pole-piece G, bolted thereto, substantially asdescribed.

In testimony that we claim the foregoing as ourown we have heretoaffixed our signatures in presence of two witnesses.

JAMES J. MGTIGHE. THOMAS J. MCTIGHE.

Witnesses D. E. DAVIS, T. J. PATTERSON.

